The victim arrived home to an empty house with Callaghan returning in an extremely intoxicated state about 10pm, when he started verbally abusing the woman, Mr Wilson said in evidence.
She took the children into her bedroom to try to get them to sleep.
However, Callaghan, who lay behind her, repeatedly spat at the woman's back and told her to leave as he was going to set fire to the house, the court heard.
On leaving the room, Callaghan went into the kitchen and put a can of milk formula on a gas element which he had lit, causing the can to heat and scorch, Mr Wilson said.
He went into the bedroom again, asking his partner to hand over the older of the children and when she refused he spat in her face before punching the wall, leaving a large fist hole in the wall.
His partner discovered the heating can of formula as she took the children to another room.
Defence lawyer Peter Stevens told the court his client had self-referred for alcohol counselling and he asked the court to consider anger management as well as supervision.
"He is making steps already ... he would like to deal with his issues."
Judge Moss told Callaghan he needed to think about the impact of his behaviour on his two young children.
"I'm sorry things went so pear-shaped. I bet you are too. Stuff happens but it's not the end of the world ... but you need to be a responsible role model for your kids. They learn from what you do. You have a lot of responsibility on your shoulders ... you need help to be able to manage yourself better."
After sentencing Callaghan to nine months' supervision she signed a protection order for his partner.
"You are joined at the hip. You share children.
"You will be parents and need to learn to do that constructively.
The judge ordered he complete a stop violence programme.
"I hope you make good use of it."
